Assiotob to btoelieb co



Patented Oct. 6, 1931 urra srA'rEs PArNr OFFICE JOSEPH H. CHEETHAM, O15 DECATUR, ILLINOIS, ASSIGNOR TO MUELLER COL, OF

DECATUR, ILLINOIS, A CORPORATION OF ILLINOIS 1 WHITE BRONZE Ho Drawing.

tics.

The alloy is particularly useful-in the man.- ufacture of bath room and plumbing articles, but is not limited to such applications, since it can be employed to take the place of the so-called white brass, German silver, and

Monel metal, as well as, many other commercial alloys sold under various trade names.

lhe alloy is characterized by possessing a color 'which is whiter than the well known 35 nickel plate, and has been found under test to resist corrosion in the atmosphere, salt waterspray, fumes and gases, as well as acids commonly found in the lavatories and water supply systems. The metal under such tests '20) has been found to be superior to any of the usual alloys employed for this purpose.

Heretofore, with most alloys it has been" necessary to cast with the greatestcare, and expert workmanship, as well as costly ma- 25 chinery and processes, have been necessary.

With the present alloy, the usual brass cast'-' v ings and cores may be employed, and no special moulding conditions are necessary. In other words, regular brass moulds are satisge factory, a particularly coarse sand is not required, and usual aggravating moulding-conditions such as venting to exit gases is eliminated.

Moreover, the melting conditions do not require any special attention, it being possible to melt the alloy in a large furnace in batches of one thousand pounds (1000 lbs.) or less, whereas with many alloys melts over one hundred and fifty pounds (150 lbs.) have been impracticable, due to the rapidity of the metal cooling below pouring temperature.

The present alloy possesses physical qualities which will be later described, which enable it to be machined at thesame speeds and feeds as regular brass or bronze, and on the same machines with identical tools.

An important feature of the invention resides in its property of permitting polishing and bufing with the same ease customary with common brass or bronze. The luster is Application filed April 16,

1929. Serial No. 355,671.

long wearing, and under careful tests, has surpassed nickel and chromium plating. If for any reason, after a long interval, a dullness appears, ordinary household cleaning compounds can be employed to restore the finish, and if the article formed of my improved alloy is kept cleaned with soap and water at regular intervals, there will be no tarnish or dullness as the metal is solid all the way through.

I have found that this improved alloy is slightly tougher than common bronzes, has equal elasticity and elongation when stretched and substantially the same hardness. A 'comparsion of a test is given below:

White Red bronze bronze Tensile strength 32,000 30,000 Elastic limit 26,000 22,000 Elongation in 2 Brinell hardness 58% 53% The composition of my improved alloy is as follows Copper to 58% Tin 0.5 to 3% Zinc ..12 to 20% Iron 0.0 to 0.75% Nickel" 12 to 19% Manganese 0.0 to 0.5% Lead 8 to 13% l have found that an alloy prepared with ingredients in the following proportions will also be quite satisfactory:

Gopper; 52 to Tin 1.5 to 2.5% Leadflm 10 to 12% Zinc 15 to 19% Iron-n; 0.0 to 0.75% Nickel 15 to 13% Manganese 0.0 to 0.25%

under mild acids and from exposure to the atmosphere. I have also determined that iron is a detriment to the metal, but cannot be eliminated, since, as stated, the purest and best copper obtainable contains a small percent of iron. For this reason, manganese is added, since the copper without the addition of the manganese would repulse the iron, and allow it to collect in large quantities throughout the mass, resulting in ruining tools when the material is being machined and in the case of pressure castings causing leakage.

Lead, as is well known, materially aids machining, but also repulses copper when in the molten state, and unless thoroughly amalgamated, produces lumps of lead segregated from the copper, generally called lead swets. For this reason, tin is employed to amalgamate the lead, since tin has an afinity for lead and copper, and the addition of a small percentage of tin up to 3% amalgamates the lead with the other elements, and the combination produces a homogeneous metal with the added advantages of maintaining for indefinite periods its silver-like luster. whiten the copper.

Zinc is used as a flux and cleaner for the copper, and materially aids foundry conditions. Its use with lead, moreover, cheapens the mixture and permits the production of a less expensive but superior alloy to many of those now in use.

As stated, no special furnaces or processes are necessary, since the melting is quite in accordance with that followed for commercial brasses and bronzes. This is a feature not heretofore possible with most of the commercially usable alloys.

As far as fluxes are concerned, no special material is required, and. this should be carefully observed, since it is the special melting and special furnaces, as well as small melts and accurate proportions of fiu'xes which render present commercial alloys so expensive and oft-times inefiicient and unsatisfactory.

The use of lead fro1n% to 13% is very important, since in many of the commercial alloys which have come to my attention the failure to appreciate properl the value and use of this ingredient has ren ered a particular alloy ruinous.

The present invention has a close resemblance in physical characteristics to commercial bronzes, and for the purpose of lavatory and plumbing fixtures and articles, is both cheaper and more commercially reliable than those heretofore used.

The proportions above given have all been found satisfactory, and if followed with reasonable care and skill will produce a white bronze of superior quality which will be more advantageous than so-called nickel or chrolhe addition of the lead acts to 7 my hand.

JOSEPH H. CHEETHAM. 

